The invention relates to a container for liquids and bulk materials in the form of a substantially parallelipipedic folding box made from cardboard, preferably from a cardboard/plastic multi-layer composite material. The container has a head portion which tapers in cross-section due to the formation of folding pockets and has the shape of a funnel with a central opening equipped with an annular shaped member.
In a prior art container of the kind specified, for example, in the container described in U.S. Pat. No. 2,321,314, the annular shaped portion engages around the top edge of the central opening on both sides and acts as a reinforcement for the edge and as an adapter for a cover closure which can be placed thereon. In the tapering head portion, two triangular folding pockets are associated with each folding line, extending into the head portion of the container, of four parallel container edges. These folding pockets lie on the outside of the head portion, so that a substantially stepless rounding of the central opening is produced inside. Due to its bowl-shaped cover, such a container is not designed or intended to be reclosed after a small quantity of the contents has been removed.
Liquids used in only small quantities in homes and industry nowadays are almost exclusively kept in plastic containers having closable spouts. Since the disposal of plastic products causes problems, for many years containers in the form of folding boxes made from a heat-sealable cardboard/plastic multi-layer composite material have been used for products, such as beverages, which are consumed not in small quantities, but all at once. However, such containers have not acquired any practical importance in connection with products that are used only in a small quantity at a time, due to the difficulty of equipping the containers with suitable spouts.
In a known container of the kind specified initially, the head portion is designed in the form of a gable roof, the spout being sealed either from inside or outside by a flange on a side of the gable roof (see, e.g., European Patent 0224539 A1, German Patent Specification 3 039 299 A1, and German Patent Specification 3 831 412 A1). A disadvantage of such containers is that they cannot be completely emptied, since the spout is placed on one side of the gable roof and not at the lowest point of the inverted container.
In contrast, another prior art container described in European Patent 0223094 A2 made from a cardboard/plastic multi-layer composite material can be completely emptied. In that container the head portion is funnel-shaped and comprises a spout inserted in the funnel-shaped portion. The funnel-shaped head portion is formed by a number of cut-out triangular areas of the cardboard blank, whose adjacent edges are interconnected via sealing seams. A disadvantage of that container is that due to the cut-out triangular areas, the funnel-shaped head portion cannot be produced without causing waste.